The invention relates to processes for analyzing aldehydes and ketones in aqueous solutions and in particular to processes for the quantitative and qualitative analyses of such aldehydes and ketones in aqueous solutions. Specifically, a need has existed for an improved method of measuring trace amounts of organic chemicals in aqueous solutions. This invention provides such an improved method for measuring aldehydes and ketones.
Measurements of trace amounts of organic chemicals in aqueous solutions have continually challenged the analytical chemist. The organic compounds must be extracted from the aqueous media, a time consuming process if the chemical is partially soluble in water. Volatile chemicals can be lost during extraction. Gas chromatography and mass spectroscopy have been used to analyze the organic compounds. In certain cases, chemicals are derivatized to enhance their measurement. Derivative formation can also require extensive sample preparations. Despite these problems, the need for accurate measurements of chemical residues in water has increased as we learn more about the effects of pollution on our environment and our health.
This invention provides a significantly new approach to the characterization and measurement of trace amounts of organic molecules in water. Radioactive derivatives of ammonia having high specific activities are used to label carbonyl compounds. The labeled compound is isolated and measured for radioactivity. The sensitivity (limits of detection) of this process are determined by the specific activity of the derivative. For example, 1 mole of acetone mixed with excess hydrazine containing 1 curie per mole would yield a hydrazone containing 1 curie or 10.sup.12 counts per mintue (cpm). An hydrazine containing 100 curie/mole yields a hydrazone containing 10.sup.14 cpm. Because radioactivity measuring devices can measure 10.sup.2 cpm with accuracy, the latter reaction would detect 10.sup.-12 mole of acetone.
Derivatives of ammonia have been used widely for many years to characterize organic compounds. The chromatographic properties of hundreds of hydrazones, phenylhydrazones, and semicarbazones have been published. Several scientists have used hydrazines to form derivatives for the gravimetric and spectrophotometric quantitation of compounds. Generally, the sensivity of these measurements is low, detecting less than 10.sup.-6 molar amounts. Never have radioactive derivatives of ammonia been used to quantitatively measure carbonyl compounds.
It is, therefore, an object of the invention to provide an improved method for measuring trace amounts of carbonyl compounds in aqueous solutions.
It is another object of the invention to use radioactive derivatives of ammonia, having high specific activities to label carbonyl compounds.
It is still another object of the invention to identify trace amounts of carbonyl compounds by chromatographic or electrophoretic methods.
Further objects and advantages of the invention will become more apparent in light of the following description of the preferred embodiments.